If you're running Cisco UCS servers, it's useful to know that the default BIOS settings are already set to support ESXi out of the box. Therefore, important settings like hardware virtualization, no execute, NUMA, and others are already configured correctly. Other server vendors may be the same, but I encourage you to verify this. The default BIOS settings on UCS servers are a balance of performance and power management. For most workloads, you can expect these settings to perform well. If you expect to run High-Performance Computing (HPC), select workloads like massive Online Transaction Processing (OLTP), or similarly unique and performance-sensitive workloads, expect to dive deeply into the vendor documentation and white papers to tune your BIOS settings accordingly.